U.S. patent number 6,916,011 [Application Number 10/182,552] was granted by the patent office on 2005-07-12 for ball valve and production method therefor.
This patent grant is currently assigned to Kitz Corporation. Invention is credited to Chikashi Gomi, Shigeo Kitazawa.
United States Patent |
6,916,011 |
Kitazawa , et al. |
July 12, 2005 |
Ball valve and production method therefor
Abstract
The invention provides a ball valve excelling in economy due to
the efforts devoted to the reduction of cost, enjoying light weight
and high reliability, manifesting high and uniform accuracy, and
enabling manufacture of compact finished products having a small
interface dimension, and provides a method for the production of
the ball valve. The ball valve includes a body formed from a pipe
having a predetermined length by subjecting opposite terminal parts
(ends) of the pipe to a plastic processing including flaring and
diametrical contraction. The body has at a central position a
seat-shaping part (seat) formed with a stem-inserting hole, a stem
inserted into the stem-inserting hole, a ball disposed
non-rotatably at a lower terminal of the stem, and a pair of
inserting members having an annular shape forced into the body from
opposite terminals of the body. Opposite terminal faces of the body
are compression-formed so that the pair of inserting members
receive and support the ball rotatably.
Inventors: |
Kitazawa; Shigeo (Yamanashi,
JP), Gomi; Chikashi (Yamanashi, JP) |
Assignee: |
Kitz Corporation (Chiba,
JP)
|
Family
ID: |
26584779 |
Appl.
No.: |
10/182,552 |
Filed: |
July 30, 2002 |
PCT
Filed: |
February 02, 2001 |
PCT No.: |
PCT/JP01/00763 |
371(c)(1),(2),(4) Date: |
July 30, 2002 |
PCT
Pub. No.: |
WO01/57423 |
PCT
Pub. Date: |
August 09, 2001 |
Foreign Application Priority Data
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|
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Feb 3, 2000 [JP] |
|
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2000-026071 |
Apr 14, 2000 [JP] |
|
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2000-114187 |
|
Current U.S.
Class: |
251/315.13;
137/15.22; 29/890.13 |
Current CPC
Class: |
F16K
27/067 (20130101); Y10T 137/0508 (20150401); Y10T
29/49423 (20150115) |
Current International
Class: |
F16K
27/06 (20060101); F16K 005/06 () |
Field of
Search: |
;251/315.1,315.13,315.14,315.15,288 ;137/15.22,315.18,315.19
;29/890.12,890.124,890.126,890.13 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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|
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|
|
|
|
62-165081 |
|
Jul 1987 |
|
JP |
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63-266276 |
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Nov 1988 |
|
JP |
|
10-122390 |
|
May 1998 |
|
JP |
|
Primary Examiner: Keasel; Eric
Attorney, Agent or Firm: Wenderoth, Lind & Ponack,
L.L.P.
Claims
What is claimed is:
1. A ball valve comprising: a body formed of a predetermined length
of pipe so as to have opposite end portions, said body having a
centrally-located seat portion, a stem-inserting hole formed in
said seat portion, and inner seal retaining parts formed at said
stem-inserting hole; a stem inserted in said stem-inserting
portion; a ball connected to a lower end of said stem so as to
rotate with rotation of said stem; and a pair of annular insert
members set at internal peripheries of respective opposite end
portions of said body; wherein said body has an outer seal
retaining part formed at each of said opposite end portions of said
body by compressing or diametrically contracting said opposite end
portions, each of said insert members being held between one of
said outer seal retaining parts and a corresponding one of said
inner seal retaining parts so that said pair of insert members
rotatably support said ball.
2. The ball valve of claim 1, wherein said stem-inserting hole has
a tubular part and a stopper projecting from said tubular part,
said stem having a flange with a notched groove to mesh with said
stopper so as to regulate rotation of said ball.
3. The ball valve of claim 2, wherein said tubular part has an
upper edge with a stepped part, further comprising packing set
against said stepped part.
4. The ball valve of claim 2, wherein said stem has a fitting
groove, further comprising an O-ring arranged in said fitting
groove, said fitting groove and said O-ring being arranged so that
said O-ring contacts an internal peripheral surface of said tubular
part.
5. The ball valve of claim 4, wherein said tubular part has an
upper edge with a stepped part, further comprising packing set
against said stepped part.
6. The ball valve of claim 1, wherein each of said insert members
has an integral outer pipe-connecting portion so as to have a
one-piece construction.
7. A method of producing a ball valve, comprising: cutting a pipe
to a predetermined length; forming a centrally-located seat portion
in the cut length of pipe; forming a stem-inserting hole in the
seat portion of the cut length of pipe; diametrically contracting a
central portion of the cut length of pipe at the stem-inserting
hole so as to form inner seal retaining parts; inserting a stem
through the stem-inserting hole; joining a ball to a lower end of
the stem inserted through the stem-inserting hole so that the ball
is rotatable with rotation of the stem; inserting a pair of insert
members at internal peripheries of opposite end portions of the cut
length of pipe; compressing the opposite end portions of the cut
length of pipe so as to form a body having an outer seal retaining
part at each end portion so that each of the insert members is held
between one of the outer seal retaining parts and a corresponding
one of the inner seal retaining parts such that the pair of insert
members rotatably support the ball.
8. The method of claim 7, wherein each of the pair of insert
members is formed so as to have an integral outer pipe-connecting
portion so as to have a one-piece construction.
Description
TECHNICAL FIELD
This invention relates to a ball valve that is fitted in a pipe for
cold or hot water, air or gas, and used therein to start, stop or
control the flow of the relevant fluid, and to a method for the
production thereof.
BACKGROUND ART
Generally, a forged or cast blank or a round bar material is cut to
form a main body, and necessary internal parts are incorporated,
screwed or bolted in the main body, thereby assembling ball valves
of this class.
These ball valves, however, are expensive because they entail high
material costs on account of large numbers of man-hours, high
prices of blanks, and large numbers of component parts, and require
high process costs for the cutting and the assemblage. They have
comparatively great weights as well. Further, since the blanks for
processed parts necessitate margins for machining in advance, the
costs of materials inevitably increase proportionately.
To cope with these problems, the concept of forming a ball valve by
resorting to the technique of press working utilizing a pipe has
been proposed. (Refer to JP-A SHO 62-165081, JP-A SHO 63-266276 and
JP-A HEI 10-122390.)
However, since the ball valve produced by the press working
technique using a pipe has a construction such that it acquires a
sealing property by having a ball tightened in a valve seat part,
such as a ball seat, which is an elastic member during the assembly
of the ball valve, the incorporation of internal components into
the pipe necessitates a step of tentative assemblage using the
internal components as an integral unit.
The ball valve, therefore, encounters the problem of adding a step
of tentative assemblage and a step of dissolving the tentative
assemblage, increasing the total number of steps of operation and
boosting the cost of production.
Even if the tentative assemblage of internal components should be
avoided, manufacturing ball valves uniformly with high accuracy as
finished products by the technique under discussion has proved
extremely difficult.
The screw connection is prevalently adopted generally for
connecting a valve with a small diameter to a pipe. When the ball
valve utilizing a pipe is joined to a pipe by the screw connection,
since the construction of this ball valve requires a screw part
different from the valve seat member to be welded to the terminal
part of the body made of the pipe or fastened to the terminal part
(expanded diametrically in advance) of the body made of the pipe,
this screw connection incurs the problem of complicating the
process of production of the ball valve and unduly elongating the
interface dimensions of the valve.
This invention which has been developed in view of the problems
mentioned above is aimed at providing a ball valve excelling in
economy due to the efforts devoted to the reduction of costs,
enjoying light weight and high reliability, manifesting high and
uniform accuracy, and enabling manufacture of compact finished
products having a small interface dimension, and is aimed at
providing a method for the production of the ball valve.
SUMMARY OF THE INVENTION
To attain the above objects, the present invention provides a ball
valve comprising a body formed from a pipe having a predetermined
length, by subjecting opposite terminal parts of the pipe to a
plastic processing including flaring and diametrical contraction.
The body has at a central position a seat-producing part formed
with a stem-inserting hole, a stem inserted into the stem-inserting
hole, a ball disposed non-rotatably at a lower terminal part of the
stem, and a pair of inserting members with an annular shape forced
into the body from opposite terminals of the body. Opposite
terminal faces of the body are compression-formed so that the pair
of inserting members receive and support the ball rotatably. In the
ball valve, the plastic processing is angular flaring work so that
the body has angular opposite terminal faces, and the paired
inserting members have similar angular outer peripheral faces.
The present invention also provides a method for the production of
a ball valve, comprising cutting a pipe in a predetermined length,
subjecting opposite terminal parts of the length of the pipe to
plastic processing including flaring and diametrical contraction,
thereby forming a body, forming a stem-inserting hole in seat
producing parts formed at an approximately central position of the
body, then forcing one of a pair of annular inserting members into
the body from one side thereof, joining a ball non-rotatably to a
lower terminal of a stem inserted into the stem-inserting hole,
forcing the other of the pair of inserting members into the body
from the other side thereof, and causing the pair of inserting
members to receive and support the ball rotatably, with a
predetermined allowance for tightening furnished for the ball,
while compression-forming opposite terminal faces of the body.
The present invention further provides a ball valve having a
construction comprising a predetermined length of a pipe having
stem-inserting holes at an approximately central position of the
pipe, stems inserted in the stem-inserting holes, a ball joined
non-rotatably to lower terminals of the stems, and a pair of
annular inserting members set on inner peripheries of opposite
terminals of the pipe. Opposite terminal faces of the pipe are
diametrically contracted or compressed to join the pair of
inserting members to the pipe and cause the pair of inserting
members to receive and support the ball rotatably.
The present invention further provides a method for the production
of a ball valve, comprising cutting a pipe in a predetermined
length, forming stem-inserting holes in the pipe at an
approximately central position thereof, inserting stems into the
stem-inserting holes, setting a ball in a non-rotatable manner to
lower terminals of the stems, setting a pair of annular inserting
members to inner peripheries of opposite terminals of the pipe and
causing the pair of inserting members to receive the ball from
opposite sides of the pipe and rotatably support the ball, and
diametrically contracting or compressing the opposite terminals of
the pipe until the inserting members and the pipe are joined.
The present invention further provides a method for the production
of a ball valve, comprising cutting a pipe in a predetermined
length, forming stem inserting holes in the pipe at an
approximately central position thereof, setting an annular
inserting member on an inner periphery of one of opposite terminals
of the pipe, and diametrically contracting or compressing the one
terminal of the pipe, thereby fixing the inserting member. Stems
are then inserted into the stem-inserting holes, and a ball is
non-rotatably joined to lower terminals of the stems. Thereafter,
another annular inserting member is set on an inner periphery of
the other terminal of the pipe, thereby causing the pair of
inserting members to receive and support the ball rotatably, and
the other terminal of the pipe is diametrically contracted or
compressed against the other inserting member, thereby joining the
other inserting member and the pipe.
The present invention further provide a ball valve comprising a
pipe of a predetermined length having stem-inserting holes formed
therein and terminals diametrically contracted to form
seal-retaining parts, a pair of seal rings (one of which is set in
one of the seal-retaining parts) stems inserted into the
stem-inserting holes, and a ball joined non-rotatably to a lower
terminal of the stems. The ball has one side thereof colliding with
the one seal ring, and the other of the seal rings is allowed to
collide against the other side of the ball. An insert ring is
incorporated on a rear terminal side of the other seal ring, and
the other seal ring and the insert ring are retained by the other
of the seal-retaining parts.
The present invention further provides a method for the production
of a ball valve, comprising cutting a pipe in a predetermined
length, diametrically contracting terminals of the pipe, thereby
forming seal-retaining parts of a tapered shape and stem-inserting
holes. One of a pair of seal rings is set on one of the
seal-retaining parts, then a ball is joined to a stem inserted into
one of the stem-inserting holes, thereby allowing one side of the
ball to collide against the one seal Subsequently, the other of the
pair of seal rings is set on the other side of the ball, an insert
ring is incorporated in the other seal ring on the rear terminal
side thereof, and then the other of the seal-retaining parts is
caused to set and retain the other seal ring and the insert
ring.
According to this invention, therefore, the attempt to allow the
product a decreased weight can be fulfilled because the product
using an inexpensive pipe as the blank for its main body has a
lighter weight than the conventional cast or forged product. Since
the product of this invention requires no cutting step as compared
with the conventional products which require cutting steps for the
sake of their main bodies, lids and various joined parts, it
permits a marked decrease in the time for production and adapts
itself for mass production as well. As a result, the cost of
production can be greatly lowered, and a ball valve veritably
excelling in economy can be produced. Further, the ball valve to be
obtained by this invention enjoys inexpensiveness and has increased
reliability because it uses a body of one-piece construction and
has joined portions and component parts in very small numbers.
The ball valve can manifest a sealing force and an operating torque
stably because it is formed by expanding the diameter and
contracting the diameter of a given pipe. Since insert members are
forced in as pressed at the opposite terminals thereof, and the
pressure welding of a ball seat to a ball is attained by uniform
exertion of pressure, the ball valve to be obtained as a finished
product enjoys high accuracy.
Further, since various members, such as the insert members and the
ball, can be inserted into the body and readied for assemblage
without requiring tentative assemblage, the time for assemblage is
shortened. Since the insert members are not required to be
furnished with portions for securing mutual distances, the ball
valve to be obtained has a decreased weight, and the insert members
incorporated therein can easily assume various states of needed
contact and facilitate adaptation of a product.
The ball valve, despite the use of a pipe, does not need to
elongate the interface dimension. Thus, the ball valve is obtained
in a compact construction composed of only a small number of
components.
In the invention described above, the ball valve is configured by
performing a burring work on a stem-inserting hole to form a
tubular part and a stopper piece projecting from part of the
tubular part, while forming a notched groove for regulating
rotation in a flange part disposed on a stem. Thus, the stopper
piece to come into working contact with the notched groove to
regulate the rotation of a ball, an O-ring fitted in a fitting
groove of the stem can contact the inner wall surface of the
tubular part, and a stepped part can be formed on the upper edge
part of the tubular part and packing can be fitted in the stepped
part.
Since the consequent impartation of the function of a stopper to
the interior of the body contributes to attainment of compaction of
the product and reduction of the cost of production and results in
integrating the body with the stopper function, the ball valve
produces an open-shut motion with increased accuracy and allows the
handle of the valve. to operate with a simple construction. Thus,
the ball valve enjoys high yield of production and veritably excels
in mass-producibility. Further, this invention warrants production
of a ball valve that adapts to widely-varied characteristics
(temperature, pressure, etc.) of a fluid and exhibits an ideal
sealing property.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is an explanatory diagram illustrating a method for the
production of a ball valve in the first aspect of this
invention.
FIG. 2 is a cross section illustrating the ball valve in the first
aspect of this invention.
FIG. 3 is a plan view of the body shown in FIG. 2.
FIG. 4 is a cross section illustrating another example of the ball
valve in the first aspect of this invention.
FIG. 5 is a plan view of FIG. 4.
FIG. 6 is a cross section illustrating an example of providing a
body. with a stepped part.
FIG. 7 is a front view illustrating a stem part.
FIG. 8 is a bottom view of FIG. 7.
FIG. 9 is a cross section illustrating yet another example of the
ball valve in the first aspect of this invention.
FIG. 10 is a plan view of FIG. 9.
FIG. 11 is a cross section of a tube having a predetermined length,
illustrating one example of a process for the production of a ball
valve in the second aspect of this invention.
FIG. 12 is a cross section illustrating, in a contracted diameter,
the neighborhood of the central part of the pipe of FIG. 11.
FIG. 13 is a cross section illustrating the state of the pipe of
FIG. 12 having internal parts incorporated therein.
FIG. 14 is a cross section illustrating a ball valve in the second
aspect of this invention.
FIG. 15 is a cross section illustrating another example of the ball
valve in the second aspect of this invention.
FIG. 16 is a partially magnified cross section of FIG. 14.
FIG. 17 is a partially magnified cross section of FIG. 15.
FIG. 18 is a plan view of the body of FIG. 14.
FIG. 19 is a cross section of the insert members of FIG. 16.
FIG. 20 is a cross section of a pipe having a predetermined length,
illustrating one example of the process for the production of a
ball valve in the third aspect of this invention.
FIG. 21 is a cross section illustrating one side of the pipe of
FIG. 20 in a diametrically contracted state.
FIG. 22 is a cross section illustrating the pipe of FIG. 21 in a
state having internal components incorporated therein.
FIG. 23 is a cross section illustrating the pipe of FIG. 22 in a
state being diametrically contracted with a jig.
FIG. 24 is a magnified cross section of a seal ring in the third
aspect of this invention.
FIG. 25 is a magnified cross-section of an insert ring in the third
aspect of this invention.
FIG. 26 is a magnified cross section illustrating the seal ring in
a state having the insert ring incorporated therein
FIG. 27 is a partially cutaway plan view of the pipe, illustrating
the relation between a stem-inserting hole and a thrust washer.
FIG. 28 is a cross section illustrating the ball valve of the third
aspect of this invention in a state being provided with a rotatable
cap nut.
FIG. 29 is a cross section illustrating the ball valve of the third
aspect of this invention in a state being provided with a soldered
cap nut.
FIG. 30 is a cross section illustrating the pipe provided at the
terminal thereof with a cap nut fitted thereto by the work of
flaring.
FIG. 31 is a cross section illustrating one example of providing
the pipe at the terminal thereof with a joining part.
FIG. 32 is a diagram illustrating another example of the body shown
in FIG. 21 in the third aspect of this invention.
FIG. 33 is a partially magnified cross section illustrating another
example of the construction for sealing the stem in this
invention.
FIG. 34 is a partially cutaway plan view illustrating another
working example of the handle.
FIG. 35 is a magnified cross section taken through FIG. 34 along
line A--A.
FIG. 36 is a referential plan view depicting the work of forming a
semi-finished product of a handle by stamping from a plate
material.
DETAILED DESCRIPTION OF THE INVENTION
This invention will be described more specifically below with
reference to the accompanying drawings. For purposes of this
description, the term "inner" means closer to the center of the
valve with respect to a central axis of the valve body (i.e., the
axis along which flow occurs), while "outer" means farther from the
center of the valve.
FIGS. 1 through 10 are intended to illustrate a method for the
production of a ball valve as contemplated by the first aspect of
this invention.
In the diagrams, reference numeral 1 denotes a pipe. This pipe 1 is
a thin-wall (non-thick-wall) type seamless pipe of copper alloy or
stainless steel. Otherwise, it may be a seamed pipe 1 produced by
shaping a steel plate in the form of a roll and then converting the
roll into a cylinder by joining the opposed edges of the roll as by
welding. A body 2 of a ball valve is formed by cutting a
predetermined length of this pipe 1, namely the length of a
prospective valve box of a ball valve, deburring the opposite ends
of the length of the pipe severed by cutting, and then subjecting
the opposite parts of the pipe 1 to the work of flaring. The
flaring work in this case consists of plastic processing an angular
(hexagonal, for example) forcing retaining part 3 that assumes a
radial plane. Further, the central position of the body 2 is
constricted or beaten to form a flat seat-shaping part 4, and a
stem-inserting hole 5 is formed in the internal region of the
seat-shaping part 4.
With reference to FIG. 2, reference numeral 12 denotes a ball
furnished with a through hole 12a. This ball 12 has a stem fitting
face 14 formed at the position for setting a stem 15. By joining a
non-circular projecting part 16 formed at the lower terminal of the
stem 15 to the stem fitting face 14, the ball 12 and the stem 15
can be joined in a non-rotary state (i.e., those parts do not
rotate with respect to each other). A flange part 17 formed in the
lower part of the stem 15 prevents the stem 15 from being flung out
by the pressure of a fluid.
Reference numeral 22 denotes a handle. This handle 22 is fixed in a
non-rotary state to the stem 15 and clamped fast with a nut 25
through a spring washer 24 and a washer 23 disposed respectively in
the upper and the lower part of the handle 22.
Numerals 6, 6 denote an example of a pair of annular insert
members. These insert members 6 are symmetrically incorporated
bilaterally relative to the ball 12. The insert members 6 each
retain on the inner peripheral side of the leading terminal part
thereof a seat ring 9 endowed with a sealing property. Due to a
sealing member (O ring) 10 made of resin and set on the outer
periphery of insert member 6, each insert member can perform the
function of a gasket against the inner peripheral face of the body
2.
The insert members 6 are each formed either by rolling a thick-wall
pipe or a thick-wall plate, then joining the opposed edges of the
roll as by welding, thereby giving rise to a metallic tube, and
cutting the tube by rolling or press working or by drawing a
thick-wall plate material into the shape shown in the diagram by
the press working. Otherwise, they may be formed by precision
casting, such as the lost-wax process, or by sintering a metallic
powder.
Further, the insert members 6 contemplated by this invention
possess such a thickness as to manifest fully satisfactory strength
during the course of joining, and also possess fully satisfactory
strength to withstand the force exerted during the forced insertion
into the pipe 1. That is, the ball valve of this invention is
directed toward allocating functions, decreasing weight and
compacting construction by adopting a configuration which derives
the strength necessary for a pressure vessel mainly from the body 2
formed of a thin-wall pipe 1 and the strength to withstand the
impact of joining pipes or of effecting the forced insertion into
the pipe 1 or the strength necessary for maintaining the bearing
stress between the ball 12 and the seat ring 9 mainly from the
insert member 6 which is a thick-wall part. The insert members 6, 6
are each furnished at the terminal end thereof on the opposite side
relative to the ball 12 with a tapered part 7 disposed at a
suitable angle along the respective angularly shaped outer
peripheral faces 8, 8. These insert members 6 may be endowed with a
suitable form of union, such as a female thread 6a that is used in
the present case. Thus, the body 2 may have suitably-incorporated
therein a portion for union, such as a female thread, without
requiring an alteration in the length of the body 2 which is formed
of a predetermined length of the pipe 1.
FIG. 3 is intended to illustrate an example of providing the body
in the interior thereof with a stopper mechanism for a handle. With
reference to this diagram, burring work is performed on the
stem-inserting hole 5 to form a tubular part 11 of a small length
and a stopper piece 13 integrally projecting from part of this
tubular part 11. Meanwhile, a notched groove 19 for regulating
rotation is formed in the flange part 17 provided for the stem 15
as illustrated in FIG. 8, and the ball 12 is disposed so as to have
the rotation thereof regulated to an angle of about 90 degrees by a
stopper mechanism formed by meshing the stopper piece 13 and the
notched groove 19. Then, by allowing an O-ring 18 inserted in a
fitting groove 15a of the stem 15 to contact the inner peripheral
face of the tubular part 11 as illustrated in FIG. 2, the ball
valve can be infallibly sealed with a compact structure. Further,
by forming a stepped part 20 on the upper edge part of the tubular
part 11 and fitting a washer 23, a gland 43 and gland packing 42 at
the stepped part 20 as illustrated in FIG. 6, the stem 15 can
retain the sealing property and increase the torque performance of
torque. In this case, the operating torque of the handle may be
relied on to disperse the force exerted on the stopper mechanism
and prevent the stopper mechanism from being deformed by providing
the flange part 17 with two notched grooves 19 indicated with a
chain line, and meshing these notched grooves 19 and the two
stopper pieces 13 as illustrated in FIG. 8.
Now, one example of the method for producing the ball valve in this
invention will be described specifically below with reference to
the drawings.
With reference to FIG. 1, the body 2 furnished with the forcing
retaining part 3 of an approximately hexagonal shape is formed by
cutting the pipe 1 in a predetermined length and subjecting the
opposite parts of the pipe 1 to plastic processing resorting to the
work of flaring.
The process of seat shaping and perforation is carried out by
drawing the approximately central position of the body 2, thereby
forming the seat-shaping part 4 and perforating the seat-shaping
part 4, thereby forming the stem-inserting hole 5. Subsequently,
burring work is performed on the stem-inserting hole 5 Due to this
burring work, the tubular part 11 and the stopper piece 13 produced
by projecting part of the tubular part 11 are formed.
Then, one of the pair of annular inserting members 6 similar in
shape to the forcing retaining part 3 is forced into the body 2
through one side thereof, and thereafter the ball 12 is
non-rotatably joined to the lower terminal end of the stem 15
inserted in the stem-inserting hole 5 as illustrated in the same
diagram. In this case, the notched groove 19 for regulating
rotation to an approximate angle of 90 degrees is formed in the
flange part 17 provided for the stem 15, and the stopper piece 13
is meshed with the notched groove 19 and incorporated in such a
manner in the body as to regulate the rotation of the ball 12.
Further, the other inserting member 6 is forced in through the
forcing retaining part 3 on the other side of the body 2.
Thereafter, the ball valve is produced by causing the seat rings 9
of the pair of inserting members 6, 6 to support the ball 12
rotatably with a predetermined tightening margin allowed for the
ball 12 and, meanwhile, simultaneously beating the terminal face
parts (diametrically contracted parts) 26 on both sides of the body
2 with jigs 47, thereby compression-forming the terminal face parts
along the contour of the tapered part 7 of the inserting member 6.
Thus, the ball 12 is supported on the seat rings 9 so as to retain
the sealing property and the property of torque as
predetermined.
The ball valve using the body 2 of such a straight type as
illustrated in FIG. 2 and FIG. 4 is produced through the process
described above. In the process involving a flaring step as
illustrated in FIG. 9, the body 2 is formed in the shape
illustrated in FIG. 9 by first circularly flaring the opposite side
parts of the pipe 1 and then flaring them in a hexagonal shape. The
rest of this process is identical with the preceding process.
In the embodiment of the ball valve of this invention, since the
construction of the ball valve varies with the bore size (ball port
diameter), it is proper to apply the construction illustrated in
FIG. 2 to the ball valve of a full port type and the construction
illustrated in FIG. 4 to the ball valve of a reduced port type.
FIGS. 11 through 19 depict a method for producing a ball valve
contemplated in the second aspect of this invention.
Like parts used in the ball valve and the method for production
thereof in the present aspect of this invention and in the
preceding aspect of the invention will be denoted by like reference
numerals and will be omitted from the following description.
In FIG. 12, is a seal retaining part 3a is formed in a tapered
shape in the pipe 2 at an approximately central position thereof by
plastic processing such as swaging or press working. The
seat-producing parts 4 are formed in a planar shape as by drawing
one each on the outside and inside of the pipe 1 at a position
close to the seal-retaining parts 3a, and the stem-inserting hole 5
is formed as well in the area inside the seat-producing part 4.
Now, the ball valve and the method for production thereof
contemplated by the second aspect of this invention will be
described below.
First, the pipe 1 is cut to obtain a length thereof needed to form
the body 2 of ball valve as illustrated in FIG. 11. Then, the pipe
1 is diametrically contracted in the neighborhood of the central
part thereof as illustrated in FIG. 12 to form the seal-retaining
parts 3a, 3a having a tapered shape. The seat-producing parts 4
having a planar shape are formed in the central part of the pipe 1
at positions close to the seal-retaining parts 3a, 3a, and the
stem-inserting hole 5 in a circular shape is formed by punching in
the area inside the seat-producing part 4.
Then, the stem 15 is inserted into the stem-inserting hole 5 from
the inner side of the body 2 and, at the same time, the ball 12 is
inserted into the pipe 1 from either of the sides thereof, with the
stem-inserting face 14 held in the direction parallel to the flow
path so as to retain the projecting part 16 of the stem 15 as
joined in a non-rotary state to the stem-inserting face 14.
The seat rings 9, 9 and the sealing members (O-rings) 10, 10 are
respectively fitted in the insert members 6, 6 as illustrated in
FIG. 14. The insert members 6, 6 are inserted into the pipe 1 from
the opposite terminal ends thereof until the seat rings 9 which are
the leading terminal parts of the inserting members 6 receive and
support the ball 12 rotatably from opposite sides The sealing
members 10 are incorporated in such a state as to contact the
seal-retaining parts 3a closely to complete a seal.
Subsequently, outer seal-retaining parts 3b, 3b are formed in a
tapered shape by diametrically contracting or compressing the pipe
1 by swaging or press working so as to substantially align the
through hole 9a of the seat ring 9 with the through hole 12a of the
ball 12 and so that the inserting members 6, 6 and the pipe 1 are
joined.
Since the seal-retaining parts 3b are formed closely along the
contour of the tapered parts 7 of the inserting members 6, they
exert a wedging effect on the inserting members 6, 6 and move the
inserting members 6, 6 slightly toward the ball 12, with the result
that the pair of seat rings 9, 9 are accurately positioned because
their mutual distance is adjusted to the predetermined magnitude.
When the sealing members 10, 10 are made to depress the inner
seal-retaining parts 3a, 3a, the inserting members 6 are aligned
more accurately because the wedging effect of the tapered shape of
the inner seal-retaining members 3a, 3a exerts a force in the axial
direction on the inserting members 6.
It would be advantageous to perform the work of diametrical
contraction or compression on the entire periphery of the outer
seal-retaining parts 3b along the contour of the tapered parts 7
thereof. So long as each outer seal-retaining part 3b is disposed
at least at one place along the contour of the tapered parts 7, the
sealing property between the inserting members 6 and the body 2 can
be retained because the sealing members 10, 10 are moved toward the
ball 12 and brought into contact with the inner seal-retaining
parts 3a, 3a. The process described above is preferably automated
with proper means, such as jigs. Further, the tapered parts 7 of
the body 2, while the valve is in use, fulfill the function of
preventing the inserting members 6 from being extracted out of the
valve by the inner pressure.
The diametrical contraction can be effected by drawing up to a
plurality of repetitions until the diameter is contracted to the
predetermined magnitude. Since the division of the work into the
plurality of parts manifests a function of increasing the strength
of the part subjected to the diametrical contraction, it is
effective in increasing the strength of the ball valve and enabling
the inserting members 6, 6 to be positioned more accurately. The
quantity of the diametrical contraction and the number of forming
processes involved in this case may be properly decided liberally
to suit the relevant operation to be performed.
FIG. 15 is a cross section illustrating another example of a method
for production of the ball valve contemplated by the second aspect
of the invention. Like parts used in the present aspect of this
invention and in the preceding aspect of the invention will be
denoted by like reference numerals and will be omitted from the
following description.
In the present example, the production is effected by a procedure
which comprises preparing the pipe 1 by cutting the pipe to a
predetermined length, forming the stem-inserting hole 5 in the
approximately central position of the pipe 1, fitting an inserting
member 6 having an annular shape in the inner periphery on one side
of the pipe 1, diametrically contracting or compressing the pipe 1
until the inserting member is fixed to the pipe 1, and then
inserting the stem 15 into the stem-inserting hole 5 and joining
the ball 12 in a non-rotary state to the lower terminal of the stem
15 as well.
The procedure further comprises fitting a second inserting member 6
of an annular shape to the inner periphery on the other side of the
pipe 1, causing the pair of inserting members 6, 6 to receive and
rotatably support the ball 12, and further diametrically
contracting or compressing the pipe 1 toward the inserting member 6
inserted into the interior of the pipe 1 on the other side until
the inserting members 6 and the pipe 1 are joined. During the
course of the diametrical contraction or compression, the
diametrically contracted parts 26 formed by diametrically
contracting the pipe 1 are meshed with depressed parts 26a disposed
at proper positions along the outer periphery of the inserting
members 6, 6 to fix the inserting members 6, 6 to the pipe 1 to
prevent them from rotating.
The depressed parts 26a are each in the form of a notched
depression having a slope 26b of a proper angle on the
tube-connecting part (outer) side of the inserting member 6, and a
substantially vertical wall on the ball 12 side as illustrated in
FIG. 17.
By diametrically contracting or compressing the neighborhood of
either of the terminal parts of the pipe 1 and then similarly
diametrically contracting or compressing the neighborhood of the
other terminal part, it is possible to move the inserting members
6, 6 by the wedging effect toward the ball 12 and bring the seat
ring 9 as aligned axially into tight contact with the ball 12.
In the embodiment of the ball valve of this invention, the ball
valve is varied in construction with the bore size (ball port
diameter) thereof. It is advantageous to adopt the construction
illustrated in FIG. 15 for the ball valve of a full port type as in
the present example, and adopt the construction illustrated in FIG.
14 for the ball valve of a reduced port type.
In either of the first and second aspects of this invention, by
providing the inserting members 6, 6 to be inserted each at the
opposite terminal portions thereof with mutually parallel external
flat parts 6b formed in an approximately hexagonal shape as
illustrated in FIG. 19, or with mutually parallel external flat
portions formed at places of an even number of not less than two
prior to the diametrical contraction or compression of the outer
periphery of the body 2, it is made possible to form mutually
parallel handle parts 2a in the neighborhood of the opposite
terminals of the body 2 as illustrated in FIG. 3 and FIG. 18 and
enable the handle parts 2a to be fixed with a fixing jig, such as a
wrench, and utilized for performing the tube fitting.
FIGS. 20 through 32 depict the ball valves and the methods for
production thereof as contemplated by a third aspect of this
invention.
In FIG. 21, a seal-retaining part 3a having a tapered shape is
formed by diametrically contracting one of the opposite terminal
parts (ends) of the pipe 2 by plastic processing, such as swaging
or press working. The seat-shaping parts 4 having a planar shape
are formed one each on the inside and the outside of the pipe 1 as
by drawing at the close to the seal-retaining parts 3a and stopping
the diametrical contraction, and the stem-inserting hole 5 is
formed in the area inside the seat-producing parts 4.
In FIG. 24, an annular seal ring made of resin is intended to
fulfill simultaneously the functions of a seat ring and a gasket of
the body 2. The ball valve uses a pair of such seal rings 27 and
they manifest the function of a gasket for closely sealing the
angular parts on the inner periphery side with a sealing part 27a
of the ball face and an outer periphery side 27b with the inner
peripheral surface of the seal-retaining part 3a of the body 2.
In FIG. 25, reference numeral 28 denotes an insert ring formed of
metal in an annular shape. This insert ring 28 has formed on the
outer peripheral surface thereof a tapered part 28a and a straight
part 28b. This tapered part 28a , due to the wedge effect generated
during the diametrical contraction of the pipe 1, increases the
accuracy of positioning of the seal ring 27 relative to the ball
12.
Then, the straight part 28b is endowed with the function of
preventing the pipe 1 and the seal ring 27 from being deformed
under the load of drawing during the diametrical contraction of the
pipe 1. In this case, when the tapered part 28a of the insert ring
28 is fitted into a fitting part 27c formed in a conical cross
section on the rear terminal face of the seal ring 27. At the same
time, the insert ring 28 is aligned by fitting a projecting part
28c of the insert ring 28 to a stepped part 27d of the seal ring 27
as illustrated in FIG. 26, the seal ring 27 follows such motions
until the seal ring 27 is incorporated in a concentric state in the
ball valve.
A thrust washer 18a is interposed between the flange part 17 and
the seat-shaping part 4 both formed at the lower part of the stem
15. The diameter of this thrust washer 18a is set at the magnitude
D that has an allowance in advance for the elliptic strain due to
the diametrical contraction of the pipe 1 (d+.DELTA.d)
(D>d+.DELTA.d) as illustrated in FIG. 27. This diameter is large
enough to avoid hindering the smooth motion of the stem.
With reference to FIG. 23, a first jig 29a is made to support the
side of the seal-retaining part 3a formed at one of the terminal
parts of the pipe 1, a second jig 29b is made to support the seal
ring 27, and forming jigs 30a, 30b are disposed on the other
terminal part side (end) of the pipe 1. With the first forming jig
30a pressing in the direction of the arrow, the pipe 1 is
diametrically contracted by plastic processing, such as swaging or
press working, and a seal-retaining part 3c is formed in a tapered
shape. In this case, by pressing the forming jig 30a across a
distance L, it is made possible to adjust the mutual distance of
(distance between) the pair of seal rings 27, 27 to a predetermined
magnitude and position the seal rings accurately.
With reference to FIG. 28 and FIG. 29, reference numeral 22 denotes
the handle. This handle 22 is attached in a non-rotary state to the
stem 15 and is provided with a stopper adapted to stop the handle
rotation at angular intervals of about 90 degrees, and is fixed by
tightening with the nut 25 through the spring washer 24 and a
washer 23 which are disposed respectively on and beneath the handle
22.
As another example, the provision of a stopper mechanism similar to
the preceding aspects of the invention is conceivable. To be
specific, the stem-inserting hole 5 is subjected to burring work to
form the tubular part 11 having a short length and a stopper piece
13 projecting integrally from part of the tubular part 11 as
illustrated in FIG. 32. Meanwhile, the notched groove 19 for
regulating rotation is formed in the flange part 17 and, due to the
stopper mechanism obtained by meshing the stopper piece 13 with the
notched groove 19, the ball 12 is disposed so as to have the
rotation thereof regulated at an angle of about 90 degree. Further,
by setting the washer 23, a gland 43 and gland packing 42 in the
upper edge part of the tubular part 11 as illustrated in FIG. 6,
the stem 15 can retain the sealing property and enjoy an
improvement in the property of torque.
FIGS. 28 through 31 depict varying examples of the joining parts
which are formed at the opposite terminal parts of the ball valve
contemplated by the third aspect of this invention.
FIG. 28 illustrates a construction produced by forming flared parts
31 one each at the opposite terminal parts (ends) of the pipe 1,
causing the leading (inner) terminal projecting parts 32a of cap
nuts 32, 32 to abut the flared parts 31, and slanting the leading
terminal projecting parts 32a of the cap nuts 32, 32 as by roller
pressing until these parts closely contact the flared parts 31.
FIG. 29 illustrates a construction produced by inserting the cap
nuts 33 into the opposite terminal parts (ends) of the pipe 1 and
joining them by welding 33a, such as soldering. FIG. 30 illustrates
an example of the construction produced by having the cap nuts 34
incorporated in advance in the opposite terminals of the pipe 1,
then flaring the opposite terminal parts of the pipe 1 to form
diametrically expanded parts 35, and allowing the cap nuts 34 to be
disposed rotatably at the positions of union as illustrated in the
diagram.
FIG. 31 illustrates a construction produced by flaring the opposite
terminal parts of the pipe 1 at an approximately right angle to
form engaging parts 36, and joining fitting parts 37a of adjoining
members 37 and the engaging parts 36 with special clamps 38.
Now, one example of the method for production of the ball valve
contemplated by the third aspect of this invention will be
described.
For a start, the pipe 1 is cut in a length for forming the body 2
of the ball valve as illustrated in FIG. 20. Then, the
seal-retaining part 3a is formed in a tapered shape by
diametrically contracting one of the terminal parts (ends) of the
pipe 1, the seat-shaping part (i.e., seat) 4 having a planar shape
is formed in the central part of the pipe 1 at a position close to
the seal-retaining part 3a, and the stem-inserting hole 5 is formed
in a circular shape by performing a punching work in the area
inside the seat-producing part 4 as illustrated in FIG. 21.
Thereafter, the seal rings 27 are inserted into the pipe 1 and set
at the positions of the seal retaining parts 3a. In this case, the
seal rings 27 manifest the function of a gasket to the body 2 by
having the outer (external) peripheral surface 27b thereof tightly
seal the inner (internal) peripheral surfaces of the seal-retaining
parts 3a.
The stems are inserted into the stem-inserting hole 5 from the
inside of the body 2 with the thrust washers 18a retained on the
flange parts 17 of the stems 15 and, at the same time, the ball 12
is inserted in the direction making the stem-fitting surfaces 14
thereof parallel with the flow path into the pipe 1 from the side
thereof not yet diametrically contracted until the projecting parts
16 of the stems 15 are connected in a non-rotary state to the
stem-fitting surfaces 14. Then, the ball 12 will collide against
the seal rings 27 in a slightly resilient state. In this case, the
seal rings 6 simultaneously fulfill the functions of a seat ring
and a gasket and contribute to the reduction of the number of
component parts of the ball valve.
Then, the other of the pair of seal rings 27 is inserted into the
pipe 1 from the side thereof not yet diametrically contracted
(second side) and, at the same time, the insert ring 28 is inserted
into the pipe 1 until the tapered parts 28a of the insert rings 28
are meshed with the fitting parts 27c of the seal rings 27 as
illustrated in FIG. 23. The various steps of the process described
above are preferably properly automated to suit the particular
construction.
Thereafter, the forming jigs 30a and 30b are set on the other
terminal part side of the pipe 1, with the jig 29a supporting the
seal-retaining part 3a formed in the first opposite terminal part
of the pipe 1 and the jig 29b supporting the seal ring 27 as
illustrated in FIG. 23. The forming jig 30b fulfills the function
of supporting the rear (outer) end of the insert ring 28 and, at
the same time, inserting the jig leading end into through hole 28d
of the insert ring 28, through holes 27e of the seal ring 27, and
through holes 12a of the ball 12 so as to align and support the
relevant members.
Then, with the forming jig 30a pressing in the direction of the
arrow, the pipe 1 is subjected to plastic processing, such as
swaging or press working, to be diametrically contracted and, at
the same time, the seal-retaining part 3c of a tapered shape is
formed. In this case, by pressing the forming jig 30a across a
distance L, it is possible to move the insert ring 3a and the seal
ring 27 slightly toward the ball 12 due to the wedging effect
generated during the formation of the seal-retaining parts 3c
having a tapered shape, and to adjust the mutual distance of
(distance between) the pair of seal rings 27, 27 to a predetermined
magnitude and position the seal rings accurately.
The diametrical contraction involved at varying steps mentioned
above may be effected by drawing up to a plurality of repetitions
until the diameter is contracted to the predetermined magnitude.
Since the division of the work into the plurality of parts
manifests a function of increasing the strength of the part
subjected to the diametrical contraction, it is effective in
increasing the strength of the ball valve and enabling the parts of
the seal rings 27 and the insert rings 28 to be positioned more
accurately. The quantity of the diametrical contraction and the
number of forming processes involved in this case may be properly
decided liberally to suit the relevant operation to be
performed.
FIG. 32 depicts another example of the body 2 shown in FIG. 21. It
represents the case of burring the stem-inserting hole 5
illustrated in the first and the second aspect of this invention to
form a stopper mechanism for the stem (handle) inside the body. The
other component parts of the present construction are similar to
those of the preceding example.
One example of the ball valve contemplated by yet another aspect of
this invention will be described below. The present example can be
applied to other aspects than the first through third aspects of
the invention. Like parts will be denoted by like reference
numerals and omitted from the following description.
In FIG. 33, reference numeral 1 denotes a pipe. This pipe 1 is a
pipe of a thin-wall type made of copper alloy or stainless steel.
Alternatively, the pipe 1 may be produced by shaping a steel plate
in the form of a roll and then joining the opposed ends of the roll
by such means as welding, thereby imparting a cylindrical form
thereto. This pipe 1 is cut in a predetermined length, namely the
length for forming a valve box of a prospective ball valve, the
opposite terminals of the length of the pipe 1 are burred, and
subsequently plastic processing is performed on the opposite
terminal parts of the pipe 1 to form the body 2 of the ball valve.
A retaining vessel 39 furnished with an angular through hole 39a
for non-rotatably receiving the stem 15 and a retaining ring 40 are
formed of a thin plate material by plastic processing, casting, hot
forging or injection molding. Then, the flange part 17 of the stem
15 to be inserted into the stem-inserting hole 5 of the body 2 is
placed in the retaining receptacle 39, a thrust washer 41 is formed
in the retaining vessel 39 on the upper side of the flange part 17,
and this thrust washer 41 is interposed between the rear side of
the seat-shaping part (seat) 4 of the body 2 and the flange part 17
as illustrated in the diagram. Meanwhile, the gland packing 42
inserted into the retaining ring 40 is positioned on the upper side
of the seat-shaping part 4 and set in the stem 15, and the nut 25
is helically fitted to the stem 15 and then fixed by tightening
through the gland 43 and the washer 23.
The construction thus obtained provides such advantages as
preventing the thrust washer 41 and the gland packing 42 from being
deformed or fractured while in service, increasing the sealing
effects thereof, and enabling them to withstand protracted use
without being affected by the characteristic properties
(temperature and pressure) of a fluid.
FIG. 34 depicts another example of the handle that can be applied
to the various aspects of this invention even when the body is not
provided therein with a stopper mechanism for the handle. This
handle is produced by deriving. an intermediate portion 45a for a
handle 45 from a plate material 44 by punching and forming a
stopper projecting piece 46 in the intermediate portion 45a by
plastic processing.
This handle enjoys a great practical value because it yields no
waste material, manifests an effect of allowing mass production and
contributes to the reduction of cost.
INDUSTRIAL APPLICABILITY
The ball valve and the method for production thereof contemplated
by this invention as described above are suitable for such a ball
valve as is set in piping for cold or hot water, air or gas, and is
operated to open or shut or control the flow of the fluid. Since
the ball valve of this invention weighs less than the conventional
counterparts made by casting, it realizes a reduction in weight of
the product and permits a great cut in the time spent for the
production and allows quantity production of ball valves. As a
result, the method of production of this invention permits a great
decrease in the cost of production and allows provision of ball
valves highly excelling in economy. Though this invention is
directed toward the ball valve and the method for production
thereof, it may be suitably applied to the formation of bodies for
valves, such as butterfly valves.
* * * * *